[Usefulness of oral exfoliative cytology for the diagnosis of oral squamous dysplasia and carcinoma]

AIM

It is well known that diagnostic oral exfoliative cytology, even if a useful, economical and practical tool in the diagnosis of oral dysplasia and carcinoma, is not yet used so extensively as is cervico-vaginal cytology.

METHODS

Exfoliative cytology was used for the diagnosis of oral dysplasia and carcinoma, and the results compared to the histological examination. Cytological smears were taken from 89 patients with oral lesions suspicious for neoplasia (in particular erythro- and leukoplakia and lichen). All patients were also subjected to oral biopsy and histological examination.

RESULTS

Out of 89 cases studied, histology showed the presence of an invasive squamous carcinoma in 32, dysplasia in 17, phlogosis in 15 and other types of lesions (2 of which malignant non-epithelial tumours) in 25. The cytological smear was inadequate for diagnosis in 11/89 cases (12.4%). In cytologically adequate and histologically positive cases, cytology confirmed the histological diagnosis of dysplasia and/or carcinoma in 38/45 cases (sensitivity 86.5%, accuracy 89.6%). Moreover, 1 case which was histologically negative at the onset, proved positive at cytology. There were 2 false-positive cytology results (specificity 94.3%, predictive positive value 95.7%).

CONCLUSIONS

Despite the small number of cases in the cohort, oral cytology can improve the accuracy of histology, and may be a useful screening tool for the diagnosis of oral neoplasia/dysplasia.

Isospin violation in epsilon'

On the basis of a next-to-leading-order calculation in chiral perturbation theory, the first complete analysis of isospin breaking for direct CP violation in K0-->2 pi decays is performed. We find a destructive interference between three different sources of isospin violation in the CP violation parameter epsilon'. Within the uncertainties of large-N(c) estimates for the low-energy constants, the isospin violating correction for epsilon' is below 15%.

[LAT (linker for activation of T cells): a useful marker for megakaryocyte evaluation on bone marrow biopsies]

Detection of atypical megakaryocytes in bone marrow biopsies, especially in cases of myelodysplastic syndromes (MDS), chronic myeloproliferative disorders (CMPD) and acute leukemias, is facilitated by staining for markers such as Ulex europaeus agglutinin (UEA)-J, CD31, CD61 and von Willebrand factor (VWF), the latter being considered the most sensitive. Recently, LAT (linker for activation of T cells), a molecule involved in T-cell activation and platelet aggregation, was found to be expressed by megakaryocytes and platelets in tissue sections. We compared VWF and LAT immunoreactivity on megakaryocytes in 64 bone marrow biopsies from 12 normal controls (NC), and from patients with MDS (n=18), CMPD (n=21) and acute megakaryocytic leukemia (AML-M7, n=13). Immunostaining was performed on paraffin sections with polyclonal antibodies against VWF and LAT. Immunoreactivity was evaluated by counting positive megakaryocytes in 10 high-power fields, and values were compared using Student's t test for paired data. Both VWF and LAT predominantly stained the cytoplasm of megakaryocytes, although LAT was also recognizable on the cell membrane. In most biopsies, the immunoreactivity of the two antibodies was quite similar. No significant differences were noticed between the mean values of VWF+ and LAT+ megakaryocytes. However, in 22 cases (5 NC; 5 MDS; 6 CMPD; 6 AML-M7), the number of LAT+ megakaryocytes was at least 30% higher than VWF+cells, while in 3 cases opposite findings were found. In 3 AML-M7 cases, anti-LAT antibodies stained numerous megakaryocytes, but anti-VWF staining was practically negative; in another 5 AML-M7 cases, anti-LAT labeling was much stronger than anti-VWF staining. LAT represents a useful immunohistochemical marker for megakaryocytes in normal and pathological conditions. It seems to be expressed by megakaryocytes more than VWF in most cases and, particularly, in conditions associated with poorly differentiated megakaryocytes, such as acute megakaryocytic leukemias. The use of LAT staining should be recommended in association with other megakaryocyte markers in the study of bone marrow biopsies in cases of hematopoietic disorders.

[Significance of the AgNOR in tumor pathology]

Analysis of silver-stained nucleolar organizer regions (AgNORs), originally regarded as a diagnostic tool, is now considered mainly as a prognostic parameter. Indeed, the expression of AgNOR proteins is associated with several biological properties of neoplastic cells: metabolic activity, DNA content, histological grade of differentiation and, especially, the rapidity of cellular proliferation. Thus, a high AgNOR quantity is a marker of aggressive tumour phenotype, and a large number of papers have shown the independent prognostic value of AgNOR analysis in several human neoplasias. Moreover, the method can be applied to small biopsies, can identify neoplastic clones with different proliferative activities and may stratify patients into different risk groups. The standardized method for AgNOR quantification offers objective and reproducible results. The evaluation of AgNOR quantity in cycling cells, either by immunohistochemistry or by a novel flow cytometry technique, may represent the future of AgNOR analysis.

Biologic differences between noninvasive papillary urothelial neoplasms of low malignant potential and low-grade (grade 1) papillary carcinomas of the bladder

We investigated the expression of oncogenes p53, c-erbB-2, and bcl-2 and cell proliferative activity in 62 newly diagnosed superficial pTa papillary bladder tumors. Based on the 1998 World Health Organization/International Society of Urological Pathology (WHO/ISUP) and 1999 WHO classifications, 19 were urothelial neoplasias of low malignant potential (LMP) and 43 low-grade (grade 1) papillary carcinomas. All the patients underwent transurethral resection and were followed up to 97 months; 42 had recurrences. Initial biopsies were tested for p53, c-erbB-2, and bcl-2 proteins using DO7, CB11, and bcl-2 124 monoclonal antibodies. Cell proliferation was assessed by MIB-1 mAb and mitotic count. LMP had significantly lower MIB-1 (p = 0.002) and p53 immunopositivity (p = 0.03), mitotic count (p = 0.006), and recurrence rates (p = 0.04) than did grade 1 cases, whereas no difference was observed for c-erbB-2 and bcl-2 expression. The median disease-free survival for LMP was 76 months but only 15 months for grade 1 cases (p = 0.002). Although the cohort is small, the results indicate that the distinction between LMP and low-grade (grade 1) papillary urothelial neoplasias, as proposed by the 1998 WHO/ISUP and 1999 WHO classifications, reflects different biologic activity and clinical behavior; however, a long-term follow-up is advisable also for patients with LMP.

Fe homeostasis in plant cells: does nicotianamine play multiple roles in the regulation of cytoplasmic Fe concentration?

The cellular and intracellular localization of the non-proteogenic amino acid nicotianamine (NA) in leaves and root elongation zones was immunochemically investigated in pea (Pisum sativum L.) and tomato (Lycopersicon esculentum Mill.) plants grown under various iron regimes and in three mutants defective in the regulation of iron uptake. Strongest immunostaining was observed in the over-accumulating pea mutants brz and dgl, and in iron-loaded wild-type plants. Fe concentration and NA level paralleled staining intensity, indicating that NA synthesis is induced by high iron availability. While label was mainly present in the cytoplasm under normal (10 microM) Fe supply and under Fe deprivation, most of the labeling was present in the vacuole in iron-loaded plants. This pattern resembled the distribution of NA in Fe over-accumulating mutants, indicating the possible importance of vacuolar sequestration in the detoxification of excess Fe. Based on the dependence of the cellular distribution of NA on the iron nutritional status of the plant, a possible role of NA in buffering free Fe in root and leaf cells was inferred. We show here for the first time that the NA concentration is increased in response to iron overload, indicating that, besides other classes of intracellular metal-binding ligands, NA may play an essential role in iron tolerance.

Tungstate Uptake by a highly specific ABC transporter in Eubacterium acidaminophilum

The Gram-positive anaerobe Eubacterium acidaminophilum contains at least two tungsten-dependent enzymes: viologen-dependent formate dehydrogenase and aldehyde dehydrogenase. (185)W-Labeled tungstate was taken up by this organism with a maximum rate of 0.53 pmol min(-)1 mg(-)1 of protein at 36 degrees C. The uptake was not affected by equimolar amounts of molybdate. The genes tupABC coding for an ABC transporter specific for tungstate were cloned in the downstream region of genes encoding a tungsten-containing formate dehydrogenase. The substrate-binding protein, TupA, of this putative transporter was overexpressed in Escherichia coli, and its binding properties toward oxyanions were determined by a native polyacrylamide gel retardation assay. Only tungstate induced a shift of TupA mobility, suggesting that only this anion was specifically bound by TupA. If molybdate and sulfate were added in high molar excess (>1000-fold), they were also slightly bound by TupA. The K(d) value for tungstate was determined to be 0.5 microm. The genes encoding the tungstate-specific ABC transporter exhibited highest similarities to putative transporters from Methanobacterium thermoautotrophicum, Haloferax volcanii, Vibrio cholerae, and Campylobacter jejuni. These five transporters represent a separate phylogenetic group of oxyanion ABC transporters as evident from analysis of the deduced amino acid sequences of the binding proteins. Downstream of the tupABC genes, the genes moeA, moeA-1, moaA, and a truncated moaC have been identified by sequence comparison of the deduced amino acid sequences. They should participate in the biosynthesis of the pterin cofactor that is present in molybdenum- and tungsten-containing enzymes except nitrogenase.

In vitro processing of the proproteins GrdE of protein B of glycine reductase and PrdA of D-proline reductase from Clostridium sticklandii: formation of a pyruvoyl group from a cysteine residue

GrdE and PrdA of Clostridium sticklandii are subunits of glycine reductase and D-proline reductase, respectively, that are processed post-translationally to form a catalytic active pyruvoyl group. The cleavage occurred on the N-terminal side of a cysteine residue, which is thus the precursor of a pyruvoyl moiety. Both proproteins could be over-expressed in Escherichia coli and conditions were developed for in vitro processing. GrdE could be expressed as full-size protein, whereas PrdA had to be truncated N-terminally to achieve successful over-expression. Both proproteins were cleaved at the in vivo observed cleavage site after addition of 200 mM NaBH4 in Tris buffer (pH 7.6) at room temperature as analysed by SDS/PAGE and MS. Cleavage of GrdE was observed with a half-time of approximately 30 min. Cys242, as the precursor of the pyruvoyl group in GrdE, was changed to alanine, serine, or threonine by site-directed mutagenesis. The Cys242-->Ser and Cys242-->Thr mutant proteins were also cleaved under similar conditions with extended half-times. However, the Cys242-->Ala mutant protein was not cleaved indicating a pivotal role of the thiol group of cysteine or hydroxyl group of serine and threonine during the processing of pyruvoyl group-dependent reductases.

Molecular analysis of the grd operon coding for genes of the glycine reductase and of the thioredoxin system from Clostridium sticklandii

A probe based on the sequence of the gene encoding selenoprotein A of glycine reductase of Clostridium sticklandii was used to obtain clones of adjacent DNA that encoded the other components of glycine reductase, proteins B and C, in addition to thioredoxin and thioredoxin reductase. The genes of the thioredoxin system and the glycine reductase were shown to be transcribed together, confirming an operon structure. In addition, a gene (grdX) encoding a 13.7-kDa protein of unknown function seemed to be associated with the reductase genes. Four potential promoters were identified by mapping the 5'-end of the mRNAs. The sequence of promoter P1 was shown to be similar to the sigma70 promoter consensus sequence. The other three promoters were similar to each other, but not to known promoter consensus sequences. The transcripts starting at each of the four promoters were terminated to about 80% at a predicted loop structure downstream of grdB; the remaining transcripts continued through this structure and covered the genes encoding both subunits of protein C and bmpA, a gene that was also expressed monocistronically.

Nuclear morphometry in male breast carcinoma: association with cell proliferative activity, oncogene expression, DNA content and prognosis

To investigate the prognostic value of nuclear morphometry in male breast carcinoma (MBC), histological samples from 50 patients (mean age 62.2 years) were retrospectively analyzed by computerized nuclear morphometry. All patients received surgery; 35 had multiple combinations of adjuvant therapies. Mean follow-up was 67 months (range 1-230). In each case, 100 tumor cells were measured, and the mean nuclear area (MNA), standard deviation of the nuclear area (SDNA), mean nuclear perimeter (MNP), standard deviation of the nuclear perimeter (SDNP) and shape factor (SHF) were calculated. Morphometric features were compared with tumor histological grade, size, nodal status, DNA ploidy evaluated by flow-cytometry and cell proliferative activity assessed by the quantity of argyrophilic nucleolar organizer region-associated proteins (AgNORs), monoclonal antibody (MAb) PC10 against proliferating cell nuclear antigen and MAb MIB-1. Comparison was also made with the immunohistochemical detection of p53, bcl-2, c-erbB-2 and c-myc proteins. Significant association was found between nuclear morphometric parameters and tumor grade, DNA content and cell proliferation indices. SDNA was greater in p53-positive and bcl-2-negative cases; SDNP was greater in p53-positive cases; SHF was lower in p53- and c-myc-positive cases. Overall survival was shorter in carcinomas with high MNA, SDNA, MNP and SDNP and low SHF. In multivariate analysis, performed by testing nuclear morphometric parameters, histological grade, tumor size, nodal status and p53 immunostaining in the Cox model, p53 over-expression and histological grade retained independent prognostic significance. When p53 was excluded, only SDNP appeared as an independent prognostic variable. Our results indicate that nuclear morphometric parameters can identify an aggressive tumor phenotype and provide additional prognostic information for patients with MBC.

Therapy and survival in male breast carcinoma: A retrospective analysis of 50 cases

The relationship between therapy and overall survival was retrospectively investigated in 50 patients with primary male breast carcinoma. Forty-five had radical or modified radical mastectomy and 5 simple mastectomy. Thirty-five received adjuvant post-operative therapy, including radiation, hormone and chemotherapy, given separately or in combination. The mean follow-up period was 67 (range, 1-230) months. The median survival was 33 months for patients receiving surgery alone and 86 months for those who also had adjuvant therapy (p=0.003). No difference in survival was found between simple or radical/modified radical mastectomy, nor among the various types of adjuvant therapy. Adjuvant therapy was most effective in large size, node positive and poorly differentiated tumors, and retained independent prognostic significance in multivariate analysis. With the limitation due to the small number of cases, our data suggest that adjuvant therapy may improve survival in males with cancer of the breast.

Oncogenes and male breast carcinoma: c-erbB-2 and p53 coexpression predicts a poor survival

PURPOSE

To investigate the prognostic value of biomarkers in male breast carcinoma (MBC).

PATIENTS AND METHODS

Fifty patients (mean age, 62.2 years) with invasive ductal carcinoma were retrospectively studied. All patients received surgery; 35 had adjuvant postoperative therapy. The median follow-up was 59 months (range, 1 to 230 months). c-myc, c-erbB-2, p53, and bcl-2 proteins were immunohistochemically detected on sections from formalin-fixed, paraffin-embedded tissues using 9E11, CB11, DO7, and bcl-2 124 monoclonal antibodies (mAbs). Estrogen, progesterone, and androgen receptors were detected using specific mAbs. Cell proliferation was assessed by MIB-1 mAb.

RESULTS

In univariate analysis, c-myc, c-erbB-2, and p53 protein overexpression was significantly correlated with prognosis. The median survival was 107 months for c-myc-negative and 52 months for c-myc-positive patients (P =.01), 96 months for c-erbB-2-negative and 39 months for c-erbB-2-positive patients (P =.02), and 100 months for p53-negative and 33 months for p53-positive patients (P =.0008). Tumor histologic grade (P =.01), tumor size (P =.02), patient age at diagnosis (P =.03), and MIB-1 scores (P =.0004) also had prognostic value. In multivariate analysis, only c-erbB-2 and p53 immunoreactivity retained independent prognostic significance. All nine patients who did not express c-erbB-2 and p53 proteins were alive after 58 months, whereas none of the 14 patients expressing both proteins survived at 61 months follow-up (P =.0002).

CONCLUSION

Overexpression of c-myc, c-erbB-2, and p53 proteins may be regarded as an additional prognostic factor in MBC. The combination of c-erbB-2 and p53 immunoreactivity can stratify patients into different risk groups.

Partial purification of an iron-dependent L-serine dehydratase from Clostridium sticklandii

An oxygen-sensitive and highly unstable L-serine dehydratase was partially purified from the Gram-positive anaerobe Clostridium sticklandii. The final active preparation contained five proteins of 27, 30, 44.5, 46, and 58 kDa as judged by SDS-PAGE. The N-terminal sequence of the 30 kDa subunit showed some similarity to the alpha-subunits of the iron-containing L-serine dehydratases from Clostridium propionicum and Peptostreptococcus asaccharolyticus. Oxygen-inactivated L-serine dehydratase from C. sticklandii was reactivated by incubation with Fe2+ under reducing conditions. Furthermore, the enzyme was inactivated by iron-chelating substances like phenanthroline and EDTA. Pyridoxal-5-phosphate (PLP) did not stimulate the activity, and known inhibitors of PLP-containing enzymes such as NaBH4 had no effect on the activity of L-serine dehydratase from C. sticklandii.

Prognostic relevance of AgNORs in tumor pathology

The importance of the analysis of the silver-stained nucleolar organizer regions (AgNORs) for prognostic purposes in tumor pathology has been reviewed. Current available data from the literature demonstrate that the evaluation of the quantity of interphase AgNORs is an independent prognostic factor in several types of human tumors. Results of our investigations indicate that AgNORs are the most powerful variable predicting survival in patients with pharyngeal carcinoma, multiple myeloma, male breast and prostate carcinoma. The combination of AgNOR counts and histologic pattern allows the stratification of patients with multiple myeloma, pharyngeal and prostate carcinoma into low- and high-risk groups, which could benefit from different therapy. Moreover, AgNOR analysis predicts response to treatment in adult patients with acute myelogenous leukemia, and appears as an independent prognostic factor in a prospective study on renal cell carcinoma. Therefore, AgNOR analysis is a really important prognostic factor for several human neoplasias. The experimental and theoretical justifications for AgNORs as a prognostic factor are also reviewed, in particular the strict correlation between AgNOR quantity and tumor cell doubling time. Lastly, the lack of prognostic significance of AgNOR analysis in some circumstances is critically discussed.

Strong enhancement of varepsilon(')/varepsilon through final state interactions

We quantify the important effect of strong final state interactions in the weak K-->2pi amplitudes, using the measured pi-pi phase shifts with J = 0 and I = 0,2. The final rescattering of the two pions provides a strong enhancement of the DeltaI = 1/2 amplitude, which so far has been neglected in the theoretical predictions of varepsilon(')/varepsilon. This correction increases the standard model prediction of varepsilon(')/varepsilon to values in good agreement with the experimental measurements.

A role for intracellular immunization in chemosensitization of tumor cells?

Acquired drug resistance represents a major cause of chemotherapy failure in patients with cancer. The characterization of the molecular pathways involved in drug resistance has provided us with new targets to overcome this problem. Many of these target proteins are often overexpressed in human cancers. A number of gene therapy strategies, including antisense oligonucleotides, ribozymes and single-chain antibodies, have been developed to achieve the selective modulation and inhibition of various cellu- lar proteins. Thus, these approaches can be exploited to modulate the resistance phenotype of tumor cells. These gene therapy strategies represent a novel and unique way to enhance the sensitivity of tumor cells to chemotherapeutic drugs. This review will focus on the use of intracellular immunization as a means to modulate the expression of specific genetic determinants involved in the drug resistance phenotype.

Identification of D-proline reductase from Clostridium sticklandii as a selenoenzyme and indications for a catalytically active pyruvoyl group derived from a cysteine residue by cleavage of a proprotein

Highly active D-proline reductase was obtained from Clostridium sticklandii by a modified purification scheme. The cytoplasmic enzyme had a molecular mass of about 870 kDa and was composed of three subunits with molecular masses of 23, 26, and 45 kDa. The 23-kDa subunit contained a carbonyl group at its N terminus, which could either be labeled with fluorescein thiosemicarbazide or removed by o-phenylenediamine; thus, N-terminal sequencing became feasible for this subunit. L-[14C]proline was covalently bound to the 23-kDa subunit if proline racemase and NaBH4 were added. Selenocysteine was detected in the 26-kDa subunit, which correlated with an observed selenium content of 10.6 g-atoms in D-proline reductase. No other non-proteinaceous cofactor was identified in the enzyme. A 4.8-kilobase pair (kb) EcoRI fragment was isolated and sequenced containing the two genes prdA and prdB. prdA coding for a 68-kDa protein was most likely translated as a proprotein that was posttranslationally cleaved at a threonine-cysteine site to give the 45-kDa subunit and most probably a pyruvoyl-containing 23-kDa subunit. The gene prdB encoded the 26-kDa subunit and contained an in frame UGA codon for selenocysteine insertion. prdA and prdB were transcribed together on a transcript of 4.5 kb; prdB was additionally transcribed as indicated by a 0.8-kb mRNA species.

Substrate-specific selenoprotein B of glycine reductase from Eubacterium acidaminophilum. Biochemical and molecular analysis

The substrate-specific selenoprotein B of glycine reductase (PBglycine) from Eubacterium acidaminophilum was purified and characterized. The enzyme consisted of three different subunits with molecular masses of about 22 (alpha), 25 (beta) and 47 kDa (gamma), probably in an alpha 2 beta 2 gamma 2 composition. PBglycine purified from cells grown in the presence of [75Se]selenite was labeled in the 47-kDa subunit. The 22-kDa and 47-kDa subunits both reacted with fluorescein thiosemicarbazide, indicating the presence of a carbonyl compound. This carbonyl residue prevented N-terminal sequencing of the 22-kDa (alpha) subunit, but it could be removed for Edman degradation by incubation with o-phenylenediamine. A DNA fragment was isolated and sequenced which encoded beta and alpha subunits of PBglycine (grdE), followed by a gene encoding selenoprotein A (grdA2) and the gamma subunit of PBglycine (grdB2). The cloned DNA fragment represented a second GrdB-encoding gene slightly different from a previously identified partial grdBl-containing fragment. Both grdB genes contained an in-frame UGA codon which confirmed the observed selenium content of the 47-kDa (gamma) subunit. Peptide sequence analyses suggest that grdE encodes a proprotein which is cleaved into the previously sequenced N-terminal 25-kDa (beta) subunit and a 22-kDa (alpha) subunit of PBglycine. Cleavage most probably occurred at an -Asn-Cys- site concomitantly with the generation of the blocking carbonyl moiety from cysteine at the alpha subunit.

Androgen receptor expression in male breast carcinoma: lack of clinicopathological association

Androgen receptor (AR) expression was retrospectively analysed in 47 primary male breast carcinomas (MBCs) using a monoclonal antibody on formalin-fixed, paraffin-embedded tissues. AR immunopositivity was detected in 16 out of 47 (34%) cases. No association was found with patient age, tumour stage, progesterone receptor (PGR) or p53 protein expression. Well-differentiated MBCs tended to be AR positive more often than poorly differentiated ones (P = 0.08). A negative association was found between ARs and cell proliferative activity: MIB-1 scores were higher (25.4%) in AR-negative than in AR-positive cases (21.11%; P = 0.04). A strong positive association (P = 0.0001) was found between ARs and oestrogen receptors (ERs). In univariate analysis, ARs (as well as ERs and PGRs) were not correlated with overall survival; tumour histological grade (P = 0.02), size (P = 0.01), p53 expression (P = 0.0008) and MIB-1 scores (P = 0.0003) had strong prognostic value. In multivariate survival analysis, only p53 expression (P = 0.002) and histological grade (P = 0.02) retained independent prognostic significance. In conclusion, the lack of association between AR and most clinicopathological features and survival, together with the absence of prognostic value for ER/PGR status, suggest that MBCs are biologically different from female breast carcinomas and make it questionable to use antihormonal therapy for patients with MBC.

Various functions of selenols and thiols in anaerobic gram-positive, amino acids-utilizing bacteria

Electron transfer reactions for the reduction of glycine in Eubacterium acidaminophilum involve many selenocysteine (U)- and thiol-containing proteins, as shown by biochemical and molecular analysis. These include an unusual thioredoxin system (-CXXC-), protein A (-CXXU-) and the substrate-specific protein B of glycine reductase (-UXXCXXC-). Most probably a selenoether is formed at protein B by splitting the C-N-bond after binding of the substrate. The carboxymethyl group is then transferred to the selenocysteine of protein A containing a conserved motif. The latter protein acts as a carbon and electron donor by giving rise to a protein C-bound acetyl-thioester and a mixed selenide-sulfide bond at protein A that will be reduced by the thioredoxin system. The dithiothreitol-dependent D-proline reductase of Clostridium sticklandii exhibits many similarities to protein B of glycine reductase including the motif containing selenocysteine. In both cases proprotein processing at a cysteine residue gives rise to a blocked N-terminus, most probably a pyruvoyl group. Formate dehydrogenase and some other proteins from E. acidaminophilum contain selenocysteine, e.g., a 22 kDa protein showing an extensive homology to peroxiredoxins involved in the detoxification of peroxides.

Bcl-2 expression in male breast carcinoma

We have analysed the expression of bcl-2 protein retrospectively in 34 primary male breast carcinomas (MBC), using the monoclonal antibody bcl-2 in formalin-fixed, paraffin-embedded tissues. Bcl-2 expression was compared with tumour clinicopathological features, sex steroid hormone receptors, DNA content, p53 immunoreactivity and cell proliferative activity assessed by counts of the argyrophilic nucleolar organizer regions (AgNORs), the monoclonal antibody PC10 against proliferating cell nuclear antigen and the monoclonal antibody MIB-1. Most (28, or 82.3%) of the 34 cases of MBC were bcl-2 positive. No association was found with clinicopathological features of the tumours, although bcl-2 tended to be more frequently expressed in small tumours (P=0.09) and in cases without necrotic areas (P=0.1). Nor was any association found with hormone receptor status, p53 immunoreactivity, DNA content, cell proliferative activity or patient survival. In multivariate analysis, only proliferative activity (expressed by AgNOR counts) and p53 immunoreactivity had independent prognostic significance. Our results indicate that MBC differs from FBC in that in MBC bcl-2 protein is not related to an oestrogen-dependent transcription pathway and bcl-2 alone is not sufficient to induce increased proliferation. These characteristics, together with the high prognostic value of cell proliferation and the lack of prognostic significance for hormone receptor status, support the hypothesis that MBC is biologically different from FBC.

Nucleolar organizer region counts predict complete remission, remission duration, and survival in adult acute myelogenous leukemia patients

PURPOSE

The analysis of the nucleolar organizer regions (AgNORs) was performed in patients with acute myelogenous leukemia (AML) to verify the role of cell proliferation in predicting complete remission (CR) and survival.

MATERIALS AND METHODS

Bone marrow biopsies from 40 adult patients with AML were stained with the argyrophilic method. The mean AgNOR number (AgNOR count) was calculated for each case. After induction therapy, patients who achieved CR received intensive consolidation; two underwent autologous and four allogeneic bone marrow transplantations (BMT).

RESULTS

The mean AgNOR count for the whole series was 6.6 (SD = 1.35); it was higher in CR patients than in resistant ones (P = .02). The median duration of CR was 26 months for patients with an AgNOR count greater than 6.6, but only 6 months for those with lower counts (P = .01). Sixteen patients who achieved a CR relapsed and 14 reached a second CR; the median duration of second CR was 16 months for patients with AgNOR count greater than 6.6, but only 5 months for those with lower counts (P = .01). The median survival time for the whole series was 14 months, with 30% of patients alive and in continuous CR at 103 months. Survival was longer for patients with an AgNOR count greater than 6.6 (33 months) than for those with lower counts (6 months; P = .0009). In multivariate analysis, when CR was excluded from the model, AgNOR count appeared as an independent prognostic variable (P = .005).

CONCLUSION

AgNOR analysis is a suitable method to assess cell proliferation in bone marrow biopsies and can predict CR, remission duration, and survival in AML patients.

Cell proliferation, bcl-2, c-myc, p53 and apoptosis as indicators of different aggressiveness in small lymphocytic lymphoma (SLL)

Cell proliferation activity, by MIB1 mAb, expression of bcl-2, c-myc and p53 gene proteins and apoptotic index (AI) were assessed in 54 cases of SLL and compared to the morphological subtypes of this disorder, defined by Lennert on the basis of amount and distribution of small and larger activated lymphocytes as diffuse, tumor-forming and pseudofollicular subtypes (DS, TFS, PFS). MIB1 scores showed significant differences between DS, PFS and TFS (5.5%, 16.61% and 24.14%, respectively; p < 0.0001). Worth noting, the MIB1 score did not differ significantly when comparing DS with the diffuse areas of PFS, or TFS with the pseudofollicles of PFS. The mean bcl-2 gene protein score was displayed to a high extent in all subtypes, but less extensively by larger activated lymphocytes that, conversely, expressed c-myc. MIB1 score correlated negatively with bcl-2 and positively with c-myc protein scores. These findings suggest that lymphocytes protected from apoptosis by bcl-2 would be exponed to cell activation and growth acceleration provided by c-myc. This condition would account for a different aggressiveness of morphologically activated subtypes, such as TFS and PFS with larger pseudofollicles. The survival analysis, performed in 23 cases, showed a trend of association of cell proliferation and c-myc expression with a more aggressive progression of the disease. Overexpression of p53 and apoptosis were found only in a minority of cases, unrelated to the subtypes. In conclusion, cell growth fraction, bcl-2 and c-myc assessment may be of help in predicting the aggressiveness of different subtypes of SLL. This approach should be most conveniently applied to PFS, which represents a continuum between DS and TFS, in order to distinguish, in this heterogeneous subtype, more indolent from more aggressive disorders.

Prognostic value of AgNOR counting

The prognostic significance of the argyrophilic nucleolar organizer regions (AgNORs) in tumour pathology is still a matter of debate. A prospective study was performed in a series of renal cell carcinomas to clarify the prognostic value of AgNOR counting. Sections from 21 renal cell carcinomas were stained in 1990 with the method of Ploton. Black dots within the nucleus from 200 tumour cells were counted: the mean AgNOR count for the whole series was 6.13, the median 5.94 and the SD 1.78. Patients were then followed up for at least 6 years or to death: at the time of the survival analysis (June 1996), 13 patients were alive without evidence of recurrence or metastasis, 6 had died of the disease and 2 of myocardial infarction. All the patients with 5.94 AgNORs per cell or fewer were alive at 6-year follow-up, while only 60% of patients with more than 5.94 AgNORs per cell survived (p=0.01). In the multivariate analysis, only AgNOR count (p=0.015) retained an independent prognostic significance. With the limitation due to the small number of cases, this prospective study clearly indicates that AgNOR count has a significant prognostic role, at least in renal cell carcinoma.

High and low risk prostate carcinoma determined by histologic grade and proliferative activity

BACKGROUND

Histologic grade of differentiation is a strong prognostic factor for prostate carcinoma. However, most tumors fall in the intermediate group. Nuclear and nucleolar morphometry and analysis of the argyrophilic nucleolar organizer regions (AgNORs) were performed to improve prognosis, especially for patients with intermediate histologic grade tumors.

METHODS

Core needle biopsies from 65 patients with primary prostate carcinoma at diagnosis were studied. Patients received only hormone therapy. Formalin fixed and paraffin embedded sections were stained with the method of Ploton. The mean AgNOR count was calculated in 100 tumor cells for each case. Nuclear and nucleolar areas from 100 cells were measured with an automated image analyzer. One-way analysis of variance and uni- and multivariate survival analyses were used for statistical evaluation.

RESULTS

In the whole series, World Health Organization (WHO) tumor grade, nuclear and nucleolar areas, and AgNOR counts were correlated with survival time. By multivariate analysis, only AgNOR counts retained independent prognostic significance. In WHO Grade 2 carcinoma, the 5-year survival rate for patients with AgNOR/cell < or = 7.84 was 77%, but was only 12% for those with higher counts (P < 0.0001). These survival rates were similar to those obtained when patients with WHO Grade 1 carcinoma and Grade 2 carcinoma plus low AgNOR counts were compared with patients with Grade 3 carcinoma and Grade 2 carcinoma plus high AgNOR counts. In Gleason intermediate Grade 6 and 7 carcinomas, the 5-year survival rate for patients with AgNOR/cell < or = 7.84 was 71%, but was only 7% for those having higher counts (P = 0.0001).

CONCLUSIONS

Nuclear and nucleolar areas, as well as AgNOR counts, supplement histologic grading in the prognostic assessment of prostate carcinoma in patients receiving only hormone therapy. AgNOR count also is a prognostic factor for patients with intermediate grade tumors. The combination of histologic grade and proliferative activity allows the stratification of patients into low and high risk groups.

Risk groups of myeloma patients by histologic pattern and proliferative activity

We investigated the histologic pattern and the cell proliferative activity of myeloma cells by the analysis of the nucleolar organizer regions (AgNORs) in bone marrow biopsy specimens from 150 multiple myelomas at diagnosis. The objective was an attempt to define risk groups of myeloma patients. On univariate analysis, the percentage of bone marrow plasma cells (BMPC%), the pattern of infiltration, the degree of plasma cell (PC) atypia, the marrow fibrosis, and the number of AgNOR/PC were correlated with survival time. On multivariate analysis, only AgNOR counts and pattern of infiltration retained independent prognostic significance. At 4-year followup, all patients with BMPC% < or = 20, interstitial pattern of invasion, and well-differentiated (G1) PC plus AgNOR/cell < or = 3.32 were alive, while no patient with BMPC% >50, diffuse pattern of infiltration, and poorly differentiated (G3) PC plus AgNOR/cell >5.15 survived (p < 0.0001). In conclusion, the histologic pattern and proliferative activity of myeloma cells, evaluated by AgNOR counts, are reliable predictors of survival in myeloma. Both parameters can be easily assessed in the same biopsy specimen, are reproducible, and permit identification of a group of patients with favourable outcome at 4-year followup. Thus, bone marrow biopsy should always be included in the diagnostic procedures for myeloma patients.

Copurification of ribosomal protein S2 and DNA-dependent RNA polymerase from heat-shocked cells of Bacillus subtilis

The DNA-dependent RNA polymerases from heat-shocked and vegetatively grown cells of Bacillus subtilis were isolated and compared. The RNA polymerase from non-stressed cells had the well known alpha, beta, beta' and sigma composition of eubacterial RNA polymerases. The RNA polymerase from heat-shocked cells exhibited one additional band shown by SDS-PAGE. N-terminal sequencing of the first 16 amino acids of the associated protein demonstrated its identity with the ribosomal protein S2.

Genetic analysis of two tomato mutants affected in the regulation of iron metabolism

Iron is one of the most important micronutrients for plants. Like other organisms, plants have developed active mechanisms for the acquisition of sufficient iron from the soil. Nevertheless, very little is known about the genetic mechanisms that control the active uptake. In tomato, two spontaneously derived mutants are available, which are defective in key steps that control this process. The recessive mutation chloronerva (chln) affects a gene which controls the synthesis of the non-protein amino acid nicotianamine (NA), a key component in the iron physiology of plants. The root system of the recessive mutant fer is unable to induce any of the characteristic responses to iron deficiency and iron uptake is thus completely blocked. We present a characterization of the double mutant, showing that the fer gene is epistatic over the chln gene and thus very likely to be one of the major genetic elements controlling iron physiology in tomato. In order to gain access to these two genes at the molecular level, both mutants were precisely mapped onto the high density RFLP map of tomato. The chln gene is located on chromosome 1 and the fer gene is on chromosome 6 of tomato. Using this high-resolution map, a chromosome walk has been started to isolate the fer gene by map-based cloning. The isolation of the fer gene will provide new insights into the molecular mechanisms of iron uptake control in plants.

DNA ploidy and p53 expression correlate with survival and cell proliferative activity in male breast carcinoma

DNA flow cytometry and the monoclonal antibody DO7 were applied in formalin-fixed, paraffin-embedded specimens from 34 primary male breast carcinomas to verify whether DNA ploidy and p53 expression were associated with survival and proliferative activity. They were compared with tumor clinicopathologic features, sex steroid hormone receptors and cell proliferative activity, assessed by the counts of the argyrophilic nucleolar organizer regions (AgNORs), the monoclonal antibody PC10 against the proliferating cell nuclear antigen and the monoclonal antibody MIB-1. A significant correlation was found between survival and tumor ploidy (median survival, 77 months for diploid but only 38 months for aneuploid cases; P = .03) and p53 expression (median survival, 95 months for cases with p53 scores < or = 14.06% versus 33 for cases with P53 scores > 14.06%; P = .0004; median survival, 99 months for p53 negative vs 39 for positive cases; P = .007). Tumor histological grade (P = .006), AgNOR counts (P = .0001), PC10 scores (P = .002), and MIB-1 scores (P = .001) were also associated with prognosis. In the multivariate analysis, only p53 scores (P = .001) or p53 immunopositivity (P = .003) and AgNOR counts (P = .022) retained an independent prognostic significance. Aneuploid tumors had higher AgNOR counts (P = .002), PC10 (P = .007), MIB-1 (P = .006), and p53 scores (P = .01) than diploid cases. A linear relationship was observed between p53 scores and AgNOR counts (r = .41; P = .014), PC10 (r = .46; P = .005), and MIB-1 scores (r = .44; P = .011). These results indicate that DNA ploidy and p53 expression are associated with survival and cell proliferative activity in male breast carcinoma. Quantitative parameters, such as DNA ploidy, p53 scores, AgNOR counts, PC10, and MIB-1 scores substantially improve the prognostic significance of the traditional parameters in male breast carcinoma.

p53 expression and proliferative activity predict survival in non-invasive thymomas

We performed p53 immunohistochemistry, DNA flow cytometry and analysis of the argyrophilic nucleolar organizer regions (AgNORs) in formalin-fixed, paraffin-embedded sections from 46 non-invasive thymomas and correlated the results with the traditional clinicopathologic features of the tumor. p53 immunopositivity was detected in 21 of 46 cases; it was not associated with any clinicopathologic features nor DNA content but significantly correlated with AgNOR counts. On univariate analysis, 10-year survival rates were 100% for p53-negative cases but only 71% for p53-positive cases and 93% for patients with low AgNOR counts but only 77% for patients with high AgNOR counts. Age, sex, histologic type, myasthenia gravis and DNA content did not correlate with survival. Our results indicate that p53 staining and evaluation of proliferative activity allow assessment of prognosis in non-invasive thymomas, when all of the other parameters are insufficient. Furthermore, the high rate of p53 expression in non-invasive thymomas suggests that abnormal p53 immunoreactivity may occur early in the neoplastic process.

Malignant cellular blue nevus: a clinicopathological study of 6 cases

BACKGROUND

Malignant cellular blue nevus (MCBN) is a rare entity due to the malignant transformation of a preexisting cellular blue nevus (CBN).

OBJECTIVE AND METHODS

The clinical and pathologic features of 6 patients with MCBN are described.

RESULTS

Three tumors were located on the scalp, 2 on the trunk and 1 on the neck. The lesions, present from birth or childhood, had enlarged rapidly in the last months before excision. Histologically, there was a dermal proliferation of spindle and epithelioid atypical melanocytic cells. Some of them were heavily pigmented. Numerous atypical mitoses were seen. In 2 cases, foci of necrosis were detected. In 2 cases, remnants of CBN were also noted. MCBN has a poor prognosis and may be difficult to differentiate from so-called atypical blue nevus, metastasis of malignant melanoma and malignant transformation of combined nevus.

CONCLUSIONS

CBN may represent a precursor of malignant melanoma. In MCBN, malignant changes seem to occur in clear cells.

Correlation between argyrophilic nucleolar organizer region counts and labelling index in multiple myeloma

The correlation between the bromodeoxiuridine (BrdU)-labelling index (LI) of plasma cells and a new proliferation marker, the Argyrophilic Nucleolar Organizer Regions (AgNORs), was investigated in 44 myeloma patients at diagnosis. A preliminary analysis was made to verify the reproducibility of the assessment of plasma cell infiltration (PC%) in bone marrow aspirates, used to collect cells for LI determination, and in bone marrow biopsies, used for AgNORs evaluation. Although an overall good correlation was observed between PC% in biopsies and aspirates (r=0.58, p=0.001), the ratio between PC% in biopsies and in aspirates ranged form 0.35 to 7.5. Only 17 patients (38.6%) were within the 0.5-1.5 range. A positive correlation between LI and AgNORs was observed in these patients (r=0.68, p=0.003), whereas the correlation was lost in patients with higher ratio between PC% in biopsies and in aspirates (r=0.08, p=0.69). The prognostic significance of AgNORs was confirmed by survival analysis, showing a reduced survival for patients with high (>4.4) AgNOR counts (14 months vs 35 months, p=0.004). The AgNORs analysis therefore allows the simultaneous evaluation of myeloma cell infiltration, degree of differentiation and kinetics of growth in bone marrow biopsies. AgNOR counts deserve to be included in the procedures for diagnosis and prognostic evaluation of myeloma patients.

Biological heterogeneity of diffuse mixed small and large cell non-Hodgkin's lymphomas assessed by DNA flow cytometry and Ki67

The cell proliferative activity of the clinico-pathologically heterogeneous non-Hodgkin's lymphomas (NHL) included in the intermediate grade F category of the Working Formulation (WF) was investigated. S-phase fraction with flow cytometry on cell suspensions, and Ki67 on frozen tissue sections were performed in 42 F NHL. An avidin-biotin immunocomplex method was used and 1000 cells from 10 representative fields were counted. DNA content, S-phase and Ki67 were also detected in 194 NHL covering the whole spectrum of the WF. DNA content anomalies were found in 52 of 194 NHL. Their incidence, like that of S-phase fraction and Ki67 positive cells, progressively increased from low- to high-grade. A linear correlation was found between Ki67 and S-phase (r = .59). Using the median value of proliferating cells obtained with both procedures as a cut off, two very different groups of lymphomas could be distinguished within a series of 42 F-intermediate NHL: with low and high proliferative cell activity (p < .0001) that were termed F(low) and F(high), respectively. A intermediate group was placed between them. It differed significantly from the others if Ki67 was used but only from the F(high) group if the S-phase fraction analysis was applied. No significant differences were seen when comparing F(low) with the single categories of low-grade NHL and F(high) with H high-grade NHL; no significant differences were found between F(high) and G, and between G and H categories. The existence of distinct groups of NHL in the F category, as defined by biological parameters assessing the cell proliferative activity, indicates that this category includes biologically heterogeneous lymphoma subtypes with different grades of aggressiveness. The results also indicate that the G intermediate category displays proliferation indices similar to those of H high grade category.

Long-term survival of thymoma patients by histologic pattern and proliferative activity

We performed DNA flow cytometry and analysis of the argyrophilic nucleolar organizer regions (AgNORs) in formalin-fixed, paraffin-embedded sections from 60 surgically resected thymomas. The results were correlated with histologic pattern, stage, associated clinical features, and survival to assess which parameters could best predict prognosis. On univariate analysis, the 10-year survival rates were 86% for predominantly lymphocytic type but only 42% for predominantly epithelial, mixed lymphoepithelial, or spindle cell thymomas (p = 0.006); survival rates were 85% for noninvasive but only 34% for invasive thymomas (p = 0.0002); 73% for diploid but only 38% for aneuploid cases (p = 0.005); 88% for thymomas with 5.75 AgNORs per cell or fewer but only 34% for thymomas with more than 5.75 AgNORs per cell (p < 0.0001). On multivariate survival analysis, tumor stage (p < 0.001) and AgNOR counts (p = 0.009) retained independent prognostic significance. The 16 patients with predominantly lymphocytic type and 5.75 AgNORs per cell or fewer were all alive at the end of the observation period. In conclusion, the histologic type of the American classification and the proliferative activity evaluated by AgNOR analysis are the best predictors of long-term survival for patients with thymoma. Both predictors can be easily evaluated in the same histologic section, are highly reproducible, and permit identification of a group of patients with a favorable outcome regardless of other clinicopathological features.

P53 overexpression correlates with proliferative activity and prognosis in carcinomas of the pyriform sinus

p53 overexpression and proliferative activity were investigated in 28 squamous cell carcinomas of the pyriform sinus of the hypopharynx prior to therapy, using DO1 and MIB-1 monoclonal antibodies in routinely processed biopsies. MIB-1 scores were associated with tumour histological grade (35.4% for grade 3 versus 23.8% for grade 2 cases; p=0.008) and survival (the median of survival was 23 months for cases with MIB-1 scores less than or equal to 33.8% but 11 months only for cases with MIB-1 scores >33.8%; p<0.001). p53 scores were associated with tumour histological grade (56.5% for grade 3 versus 37.1% for grade 2 cases; p=0.02) and survival (median of survival 20 months for cases with p53 scores less than or equal to 56.2% versus 11 months for cases with p53 scores >56.2%; p=0.002). Tumour histological grade was also correlated with prognosis (median of survival 50 months for grade 2 versus 14 months for grade 3 cases; p=0.03). In the multivariate analysis, only MIB-1 (p=0.001) and p53 scores (p=0.003) had an independent prognostic significance. A linear relationship between p53 and MIB-1 scores was observed (r=0.54; p=0.012). With the limitation due to the small number of cases, our findings indicate that p53 overexpression correlates with proliferative activity and survival in squamous cell carcinomas of the pyriform sinus, and suggest the use of p53 and MIB-1 immunostainings in the pretherapeutic assessment of the tumour aggressiveness.